According to the report, illegal detention and enforced disappearances are routine in Sri lanka, with the government abusing laws drafted to combat the LTTE.

The LTTE had a horrific record of abuse, including killing and imprisoning its critics, but that did not, and does not, excuse the widespread and systematic mistreatment of detainees by the Sri Lankan government, Amnesty International's Asia-Pacific Director Sam Zarifi said on the group's website.

The security regime that was a hallmark of war continues after the LTTE's defeat -- little has changed. Authorities take advantage of laws allowing them to imprison people for months or years, with no need for prosecution in a court of law.

A lack of accountability for alleged war crimes gives the green light to Sri Lankan authorities to act with impunity. Meanwhile the message coming from the Sri Lankan government is that those who dare criticize it risk harassment, or even disappearance, he said.

According to Agence-France Presse, rights groups estimate up to 40,000 civilians were killed in the final stages of the Sri Lankan civil war.

According to Zafri, The message coming from the Sri Lankan government is that those who dare criticise it risk harassment or even disappearance.

The report comes as Sri Lanka seeks to derail a move by the U.S. to introduce a draft resolution at United Nation's Human Rights Council, increasing international pressure on Colombo to conduct an independent investigation.

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